Inverter is an electronics device that help to convert direct currents (DC) to alternating currents (AC). The circuit with the help of oscillator helps to fluctuate the Direct current to reach a certain frequency at which the currents will be convert to alternative currents. People that are not inclined do mistake inverter for rectifier: The difference between rectifier and inverter is that Inverter is for converting direct current to alternative current while rectifier for converting alternative current to direct current for storage An oscillator is an instrument for producing Voltages that vary in a regular fashion; the waveforms of the voltages are repeated exactly in equal successive intervals of time. In many cases the waveform of the output voltage is sinusoidal and the oscillator is then called a sine wave generator or harmonic oscillator. Those instrument that produce repetitive waveforms that are square, triangular or saw tooth in shape are called relaxation oscillators. The term relaxation is used because during the generation of the waveform there is a period of activity in which there is a sharp transition from one state to another. This period is then followed by relatively quiescent one, after which the cycle in nature, the most common one being the heart. Oscillator can be constructed so as to operate at frequencies as low as one or two cycles an hour or as high as hundreds of megahertz. The selection of a suitable frequency or range of frequencies depend upon the function that the oscillator is required to perform. Crystal oscillator There are several applications, notably in telecommunications systems and in laboratory frequency – standard equipment, where highly stable frequencies are required. Frequency drift in oscillators is due to changes in the resonant frequency. www.techrib.com.ng/2018/01/how-to-make-100-watts-inverter-using.html?m=1